Reading this blog of yours made me remember the topics in our Science class that were taught during my High School years. I am quite familiar with the terminologies you used and I'm glad that I still remember them! It just means that there is some knowledge retained in my mind even though years passed by.
Since you mentioned that plants need nutrients or fertilizers to grow which is completely essential for a living organism. I want to share what my biology teacher shared with us, you probably know this already but I still want to share. Lol.
Eggshells are a great source of nitrogen for plants. When I heard it from her I applied it to our plants at home and still doing it today. I collect all the eggshells first, dry them in the sun, and after that pulverized them. Then it's now ready to be sprinkled on plants' soil!